U.S. patent number 5,046,474 [Application Number 07/519,095] was granted by the patent office on 1991-09-10 for crankcase ventilator/evacuation system.
Invention is credited to Donald W. Percy.
United States Patent |
5,046,474 |
Percy |
September 10, 1991 |
Crankcase ventilator/evacuation system
Abstract
A crankcase fumes treatment apparatus envisions a primary
filtering system for extracting fuel, moisture and solids from the
engine crankcase, the solids being mainly trapped by a filter
element preventing reentry into the engine, with the fuel vapors
and moisture being conducted returnably to the engine for
increasing horsepower and a secondary filtering system for
secondarily filtering the fuel vapors from solids before passage to
the engine.
Inventors: |
Percy; Donald W. (Londonderry,
NH) |
Family
ID: |
24066808 |
Appl.
No.: |
07/519,095 |
Filed: |
May 4, 1990 |
Current U.S.
Class: |
123/573;
123/572 |
Current CPC
Class: |
F01M
13/04 (20130101) |
Current International
Class: |
F01M
13/04 (20060101); F01M 13/00 (20060101); F02M
025/00 () |
Field of
Search: |
;123/572,573,574 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Dolinar; Andrew M.
Assistant Examiner: Macy; M.
Attorney, Agent or Firm: Ross, Ross & Flavin
Claims
I claim:
1. Vacuum-controlled apparatus for removing contaminates from fumes
and vapors emanating from the crankcase of a diesel engine and for
returning the cleansed vapors to the engine combustion chamber and
consisting of an in seriatim series of filter stages
comprising:
a primary filter stage including
a rocker arm bonnet fitted to the engine rocker arm and
communicating therewith, sand
a series of layers of filter elements disposed within the bonnet
and arranged as a stack of layers in face-to-face confrontation as
to each other with the layers differing in porosity from a most
coarse inboard layer to a most fine outboard layer with a layer of
intermediate porosity sandwiched therebetween,
a secondary filter stage including
a secondary housing,
a first conduit interconnecting the primary stage filter and the
secondary housing into which it is extendable,
a magnetic disc within the housing and circumscribing the first
conduit,
a seal at the upper extremity of the first conduit for directing
the incoming flumes and vapors from the first conduit into the
housing and past the magnetic disc for the capture of any ferrous
particulates therewith,
a filter cartridge spaced upwardly of the disc,
housing seal means for forcing all fumes and vapors through the
filter cartridge for the capture of the non-ferrous particulates
therewith preliminary to discharge from the secondary housing,
an apertured core tube disposed centrally of and within the filter
cartridge, and
an outlet in the secondary housing communicating with the core tube
for the discharge of the filtered fumes and vapors from the
secondary housing,
a tertiary filter stage including
a tertiary housing,
a second conduit interconnecting the secondary stage outlet and the
tertiary housing,
a filter element disposed within the tertiary housing,
a fan disposed beneath the filter element, and
an activator plate disposed beneath the fan,
and a compressor having a vacuum side connected to the tertiary
housing and a pressure side connected to the engine intake manifold
for the forced in seriatim withdrawal of the fumes and vapors from
the rocker arm and through the primary and secondary and tertiary
filter stages and returnably to the engine intake manifold.
Description
BACKGROUND OF THE INVENTION
This invention relates to new and useful improvements in a
ventilation system for the crankcase of an internal combustion
engine.
1. Field of the Invention
Blow-by gases and vapors, such as moisture in the form of steam,
hydrocarbons, and unburned fuel, enter the crankcase lubricating
oil chamber during IC. engine operation, the gases and vapors
occuring because of leakages past the piston rings during operation
cycles.
If not removed as fast as they are introduced into the crankcase,
contamination of the lubrication oil ensues. This condition has
existed since the first IC engine was put into service.
Lubricants are formulated with an additive package for the purpose
of suspending and emulsifying extraneous particles picked up from
the atmosphere and blow-by vapors, plus gums, varnishes, tars, and
acids generated by the combustion process.
Ventilating or scavenging crankcase systems in the past have
attempted to provide a method for removing these undesirable
particles into the atmosphere by a pressure method.
In normal operation of a reciprocating I.C. engine there is a
certain amount of crankcase vapors, continually being developed.
These consist in part of gaseous combustion products entering the
crankcase by passing between the piston rings and cylinder walls,
valve guides and valve stems. This particular portion of the
crankcase vapors is often referred to as blow-by.
The crankcase vapors are normally comprised of, fuel, moisture
hydrocarbons, soot combustible materials such as atomized oil,
diesel fuel, and heavy particulate resulting from engine
operation.
The releasing of such vapors and gases into ambient atmosphere is
directly related to the development of a smog atmosphere.
Obviously, the development of a means for reducing air pollution
due to engine operation is a desideratum.
2. Description of the Prior Art
Numerous devices are known to the prior art which function to
remove crankcase vapors and the like from the crankcase and pass
same into the air carburetor and filtering system or intake
manifold thereof unfiltered. For the most part, these crankcase
vapors handling devices use a pushing or self-developed pressure
method to release the vapors from the crankcase into the intake
manifold without filtering or treating same, which my system
does.
Thus, by so doing impregnating the lubricant with contaminates is
eliminated, oil usage is prolonged, and less consumption is
accomplished.
Some systems have been provided by establishing communication
between the crankcase interior and the vacuum process now existing
in the engine intake manifold. These systems, however, are plagued
with the problem of adequate volumetric control of the undesirable
vapors, solids and so on, under all conditions of the engine
operation.
An apparatus for treating crankcase vapors is now known of which
provides for directly removing the crankcase vapors from the
crankcase into the intake manifold of the engine. While it removes
the crankcase vapors from the engine, it does not substantially
increase the hydrocarbon exhaust pollution due to the crankcase
vapors being passed through the engine combustion system because of
a depth packed filtering processing system before being introduced
to the atmosphere.
Another known apparatus utilizes an indirect exhaust manifold heat
exchanger to warm the vapors before they are introduced into the
engine intake. Such a heat exchanger is known in the prior art as
having a low efficiency which only slightly warms the vapors before
they are introduced into the engine. The process of warming
crankcase vapors and introducing them directly into the engine
intake does not make them more significantly suitable for
combustion to pollute the atmosphere.
With a gas engine running at idling speed and minimum load
conditions, the throttle valve of the carburetor is substantially
closed and hence, develops a maximum vacuum downstream of the
throttle valve. During such a phase of engine operation, there is a
minimum of leakage of gases, vapors and solids into the crankcase
chamber. Like the prior application, a diesel engine has little
vacuum in the intake air system at idle, this being the necessity
of the compressor in constant use as is the operation of the
evaculator system.
This constantly keeps the presence of moisture and diesel vapors in
the crankcase at a negative state, which in turn minimizes the
dilution of the lubricant and significantly reduces oil consumption
previously being pushed out of the breather tube in the form of
vapors, and at the same time eliminating back pressure to the
underside of the pistons, stabilizing the overall performance of
the engine. One half pound PSI of constant crankcase back pressure
is equal to 86# of drag at all the running time of engine.
In a gas application with the throttle moved to a loaded or more
fully-opened position, the manifold vacuum pressure approaches
atmosphere effective conditions. At the same time the amount of
blow-by gases, vapors and solids emitted into the crankcase and
related chambers is substantially increased.
Ergo the need for an efficient crankcase evaculating system capable
of constantly: 1. volumetrically controlling the vacuum of the
crankcase back pressure, 2. versus ambient atmospheric pressure, 3.
intake manifold vacuum and 4. blown air pressure.
In the case of turbo-powered diesel engine power plants, when the
engine is under full load the blower is pressurizing the air into
the intake manifold. This is the substantial explanation of the
difference between this process hereof and the known prior art--#1
In order to remove the so-called fumes from the crankcase ; #2
filtering them to a cleaner state of condition than originally
used; #3 the compressor as is adopted in this process is to
accommodate three requirements at the same time,that being:
1. evacuating the fumes from the crankcase
2. drawing them through an effective depth-type filtering system
and
3. exceeding the air pressure that is being exerted in the intake
manifold by the engine blower.
If such a condition is not maintained constantly, a back lash will
take place on the evaculator process, that is why the metered
pressure from the compressor into the intake manifold has to exceed
that of the blower of the engine at all times, supplying additional
air and clean atomized fuel to generate additional horse power.
The embodiment of the crankcase fumes treatment apparatus of the
present invention envisions a dynamic depth-type filtering system
which cleans fuel vapors, and moisture, also non-ferrous solids
from the engine crankcase blow-by. The solids are trapped by the
filter element which prevents them from reentry to the engine
intake manifold in contrast to prior art 2. However, the fuel
vapors contained in the blow-by are cleaned and reused by the
engine to general horsepower. By extracting the solid contaminants,
porous and nonporous particulate but reintroducing cleaned diesel
vapors to engine, wear is reduced, horsepower is increased, and the
useful life of crankcase lubricant is prolonged and consumption is
reduced. Returning fuel vapors to the engine intake manifold
increases engine horsepower performance and fuel efficiency
dramatically.
The invention provides a crankcase fumes treatment apparatus having
a crankcase vapors and solids trap communicably connected with an
I.C. engine between the crankcase and the intake manifold which in
use will pass the resulting vapors into the intake manifold of the
connected engine.
The system offers suitable application in diesel-driven trucks,
tractors and buses, diesel-driven marine vessels and industrial
generators of all types. Such a system can be modified to work very
satisfactorily on automotive applications.
SUMMARY OF THE INVENTION
The embodiment of the crankcase fumes treatment apparatus of the
invention envisions a dynamic filtering system which cleans the
fuel and the moisture and eliminates the solids from the engine
crankcase blow-by. The solids are trapped by a filter system which
prevents them from reentering the engine. However, fuel vapors
contained in the blow-by are reused by the engine. By extracting
the contaminants, such as ferrous particles, engine wear is reduced
and the useful life of the crankcase oil is prolonged. Returning
the fuel vapors to the engine manifold dramatically increases
engine horsepower, performance and fuel efficiency.
The invention provides a crankcase fumes treatment apparatus having
a crankcase vapors trap communicably connected with an I.C. engine
between the crankcase and the intake manifold which in use will
pass crankcase vapors into the crankcase vapors trap and therein
separate liquid portions thereof from gaseous portions thereof and
pass the resulting vapors into the intake manifold of the connected
engine.
The system offers suitable applications in diesel-driven trucks,
tractors and buses, diesel-driven marine vessels and industrial
diesel generators of all types.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded schematic diagram showing the key components
of the system; and
FIG. 2 is a sectional view through the secondary filter assembly of
the invention showing its components in assembled position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 advantageously serves as a flow diagram of the ventilating
system of the invention.
Directly connected to each rocker arm 2 is a rocker arm bonnet 4
which contains a sealed set of replaceable multi-stage filters 6,
same representing a plurality of layers of filtering material
arranged in the order of descending porosity to define a
monolithic, layered porous structure. The layers of different
permeabilities and porosities are formed by placing the layers of
controlled retention characteristics across the interior diameter
of rocker arm bonnet 4.
The rocker arm bonnet represents the primary filter stage.
The multilayered primary microfiltration medium consists of a
series of filter elements each comprised of reticulated airfoam
"honeycomb" material consisting of a three-dimensional network of
interconnecting strands of a polyurethane resin. Each element abuts
the next in face-to-face confrontation and is longitudinally
aligned with the others. Each varies in porosity from a most coarse
inboard layer 8 to a layer of finest porosity 12 as the outboard
layer in the direction of airflow through the bonnet, with a layer
of intermediate porosity 10 sandwiched between layers 8 and 12.
Filters 8, 10, and 12 are interengaged as by a spindle means 14
extendable through the bank of the filters of the set and having a
finger engaging portion by which the filters may be removed
unisonly from the bonnet for any replacement or cleaning
purpose.
An apertured cover 16 is nestably receivable over the open top of
rocker arm bonnet 4 to tightly enclose same.
The blow-by vapors are led into the rocker arm bonnet for the
primary filtration.
A connecting conduit 60 leads from the bonnet interior and through
its cover 16 to the lower extremity of a secondary subassembly now
to be described.
The filtered blow-by vapors are passaged from the primary stage to
the secondary stage 18 via conduit 60. The conduit extends through
a suitable opening in the bottom wall of a lower housing half part
or canister 64.
The secondary stage is termed an evaculator. Conduit 60 is provided
with a plurality of equispaced raw vapor inlet ports 62. A magnetic
disc 66 circumscribes conduit 60 and seats upon the inner wall of
the bottom of lower housing half part 64. Inlet ports 62 are
disposed upwardly of magnetic disc 66.
Spaced upwardly of magnetic disc 66 and also circumscribing conduit
60 is a baseplate baffle 68 having a lowermost radially extending
circular portion upon which seats a filter gasket 70.
A plug 73 seals off the upper extremity of conduit 60 to influence
the passage of the incoming fumes and vapors radially over the face
of magnetic disc 66 and into the open space 74 between a filter
cartridge 72 and lower housing half part 64.
As the vapors enter through the conduit, they are confronted by the
baffle serving to direct the vapors over the magnetic disc which
picks up the ferrous particles therein contained, with the
non-ferrous particles and moisture being subsequently trapped by
filter cartridge 72. That is, the ferrous particulates are captured
by the magnetic system upon entry into the sealed secondary stage,
while the non-ferrous abrasives continue on in a vacuum atmosphere
only to be trapped by the filter cartridge.
Filter cartridge 72 seats upon gasket 70 whereby it is spaced
upwardly of the bottom flooring or deck of the lower housing half
part to define space 74.
An upper housing half part 76 mates with the lower housing half
part 64 at the midsection of the housing, the two components being
suitably sealed with an annular U-shaped locking ring 78.
Upwardly of conduit 60 and extending vertically through a provided
central opening in filter 72 is a core tube 80 having an interior
thread and into the lower end of which plug 73 is threadedly
engaged and plug welded thereto.
With the upper extremity of core tube 80, a filter retainer 82 is
threadedly engaged, same being sealed against the interior of the
top wall of the upper housing half part by an O-ring seal 84,
strategically positioned between filter retainer 82 and an outlet
86 extending through the top wall of and leading from the upper
housing half part.
An annular filter element gasket 88 is interposed between filter
retainer 82 and the top of filter 72 to insure against leakage of
any of the vapors and fumes except by passage through the filter
and core tube 80 and retainer 82 before exiting via the outlet port
86 as filtered vapors.
An O-ring seal 85, additional to O-ring seal 84, in the lower half
of the canister aids to insure the prevention of the vapors from
escaping secondary filtration.
A crankcase oil return port 92 is provided in the bottom wall of
lower housing half part 64 to which a crankcase oil inlet 94 is
threadedly connected.
An anti-syphon valve 96 is disposed outboard of crankcase oil inlet
94 and in which an upper float ball 98 and a connected anti-syphon
ball 100 are disposed.
The buoyancy of the oil when present in the antisyphon valve 96
lifts the twin balls 98-100 from the seat of the lower float ball
on the crankcase oil outlet port 102 so as to allow the return of
the crankcase oil to the engine crankcase. This operation takes
place only when excess blow-by in engine crankcase is above normal
causing a high concentration of oil accumulation of oil in the
lower half of the secondary housing.
The remaining filtered fuel and moisture vapors are exited from the
secondary stage via outlet 86 and a threadedly connected conduit
100 to a tertiary filter subassembly, as shown in FIG. 1.
Conduit 100 leads into and through a wall 102 of a clear
see-through tertiary stage filter housing 104 in which is disposed
a filter element 106.
Within the housing and adjacent filter element 106 a free-spinning
fan 108 is provided, same being operable rotatively by virtue of a
series of small holes 110 in an activator plate 112, the plate 112
and fan 108 being mounted on a shaft 114.
The fan functions as an indicator of the airflow. When and if the
fan slows down in its rotative motion, or ceases rotation, the
delivered intelligence is to the effect that a change in filters is
indicated.
A cover wall 118 permits the enclosing of the third stage filter at
its opposite end.
The third stage assembly performs a pair of essential functions; it
acts as a flow indicator filter to be sure, but more importantly,
it serves as an indicator of the overall system performance.
The housing, being clear, it is possible to see into same to
determine the activity of the free-spinning fan blade. Thus, the
overall performance of the system can be assessed.
The color of the third stage filter unit is an indicator of the
whole system performance. A discolored filter indicates the
presence of varnish or soot and that the filter element should be
replaced. The free-wheeling fan rate of turning indicates a direct
ratio to the engine fume flow and is a good indicator of system
performance. The fan free wheeling means that vapors are moving
through the system, and the system is functioning
satisfactorily.
The output of the third filter assembly connects via a conduit 120
to the vacuum side of a compressor 122 which provides a vacuum
sufficient enough to draw the cleaned vapors through the system.
The pressure side of the compressor connects via conduit 124 to the
intake manifold 126 of the engine.
Thereby, the fuel being introduced from the crankcase, as so called
blow-by, has been cleansed by the system and returned to the engine
creating increased horsepower for use, thus, better fuel
economy.
* * * * *